trigonometric eqn

13:14

11:34

15:37

13:59

4:48

10:37

3:56

1:32

3:19

8:42

6:01

5:57

8:56

4:58

28:06

9:29

5:56

1:57

4:33

4:33

13:50

1:53

1:16:47